Question

Slipped, mispaired DNA occurs when the DNA region has A. direct repeats. B. homopurine-homopyrimidine sequences. C. inverted repeats. D. mirror repeats. E. palindromes.

Short answer

A. Direct repeats B. Homopurine-homopyrimidine sequences C. Inverted repeats D. Mirror repeats E. Palindromes Answer: B. Homopurine-homopyrimidine sequences

Step-by-step solution

Analyze the options

We need to check each option and analyze if it describes slipped, mispaired DNA. A. Direct repeats refer to a type of repetitive DNA, but not the type that would cause mispairing. B. Homopurine-homopyrimidine sequences are DNA regions with a high content of purines (A and G) or pyrimidines (C and T) on one of the strands. These sequences can cause slipped mispairing due to strand slippage during DNA replication. C. Inverted repeats are regions of DNA that have the same sequence but in reverse orientation. Inverted repeats can fold back on themselves to form hairpin or cruciform structures, but they do not cause slipped mispairing. D. Mirror repeats are similar to inverted repeats but with a more restrictive definition. They do not cause slipped mispairing as well. E. Palindromes are DNA sequences that read the same from both directions. Palindromes often do not cause slipped mispairing.

Choose the correct answer

Based on the analysis of the options, the correct answer to the question is: B. Homopurine-homopyrimidine sequences Homopurine-homopyrimidine sequences can cause slipped, mispaired DNA due to strand slippage during DNA replication.